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Without doubt this book is unique amongst general texts on immunology.In their preface the authors tell us that they believe it to be "a remarkably unusual book".In the sense that it breaks new ground in the powerful visual appeal of its illustrations, it is.In other regards, however, it takes a well-tried and successful route in describing the subject.There are twenty-five chapters which take the reader from the general principles of adaptive and innate immunity through the cells and molecules of the immune system to the principles and features of immunity to infection,
When Fe2+ ions are added to rat-liver microsomes, lipid peroxidation begins after a short lag period. Fe2+-dependent peroxidation in the first few minutes of the incubation can be increased by adding Fe3+, ascorbic acid or Pb2+ ions; these stimulations are not additive. By contrast, Pb2+ ions inhibit peroxidation of microsomes in the presence of Fe3+/ascorbate or Fe3+-ADP/NADPH. In liposomes made from ox-brain phospholipids, Fe2+-dependent peroxidation is stimulated slightly by Fe3+, but much more so by ascorbic acid, Al3+ or Pb2+; these stimulations are not additive. Liposomal peroxidation in the presence of Fe3+/ascorbate is inhibited by Pb2+ or Al3+. These results argue against the participation of an Fe2+-Fe3+-O2 complex, or a critical 1:1 ratio of Fe2+ to Fe3+, in the initiation of lipid peroxidation in liposomes and rat-liver microsomes.
Conference Article| December 01 1978 Oxidation of Thiol Compounds by Catalase and Peroxidase in the Presence of Manganese(II) and Phenols JOHAN DE RYCKER; JOHAN DE RYCKER 1Department of Biochemistry, University of London King's College, Strand, London WC2R 2LS, U.K. Search for other works by this author on: This Site PubMed Google Scholar BARRY HALLIWELL BARRY HALLIWELL 1Department of Biochemistry, University of London King's College, Strand, London WC2R 2LS, U.K. Search for other works by this author on: This Site PubMed Google Scholar Biochem Soc Trans (1978) 6 (6): 1343–1345. https://doi.org/10.1042/bst0061343 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Cite Icon Cite Get Permissions Citation JOHAN DE RYCKER, BARRY HALLIWELL; Oxidation of Thiol Compounds by Catalase and Peroxidase in the Presence of Manganese(II) and Phenols. Biochem Soc Trans 1 December 1978; 6 (6): 1343–1345. doi: https://doi.org/10.1042/bst0061343 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Society Transactions Search Advanced Search This content is only available as a PDF. © 1978 Biochemical Society1978 Article PDF first page preview Close Modal You do not currently have access to this content.
1. No evidence could be found for production of the superoxide radical, O2-, during autoxidation of ascorbic acid at alkaline pH values. Indeed, ascorbate may be important in protection against O2- genat-d in vivo. 2. Oxidation of ascorbate at pH 10.2 was stimulated by metal ions. Stimulation by Fe2+ was abolished by superoxide dismutase, probably because of generation of O2-- during reduction of O2 by Fe2+, followed by reaction of O2-- with ascorbate. EDTA changed the mechanism of Fe2+-stimulated ascorbate oxidation. 3. Stimulation of ascorbate oxidation by Cu2+ was also decreased by superoxide dismutase, but this appears to be an artifact, since apoenzyme or bovine serum albumin showed similar effects.
Research Article| October 01 1972 Flavin mononucleotide-sensitized photo-oxidation of glyoxylate in Good's buffers. (Short Communications) B Halliwell; B Halliwell 1Botany School, University of Oxford, South Parks Road, Oxford OX1 3RA, U.K. Search for other works by this author on: This Site PubMed Google Scholar V S Butt V S Butt 1Botany School, University of Oxford, South Parks Road, Oxford OX1 3RA, U.K. Search for other works by this author on: This Site PubMed Google Scholar Biochem J (1972) 129 (5): 1157–1158. https://doi.org/10.1042/bj1291157 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Cite Icon Cite Get Permissions Citation B Halliwell, V S Butt; Flavin mononucleotide-sensitized photo-oxidation of glyoxylate in Good's buffers. (Short Communications). Biochem J 1 October 1972; 129 (5): 1157–1158. doi: https://doi.org/10.1042/bj1291157 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Journal Search Advanced Search This content is only available as a PDF. © 1972 London: The Biochemical Society1972 Article PDF first page preview Close Modal You do not currently have access to this content.
The new edition of this well-established book is thoroughly revised and gives a comprehensive account of the role of free radicals, other reactive species (RS), and antioxidants in life, health, and disease. Chapter 1 reviews how oxygen (O2) is used by living organisms, why it can be toxic, and introduces the concept of oxygen radicals and other RS; their chemistry is detailed in Chapter 2, especially for superoxide, hydroxyl radical (including Fenton chemistry), peroxynitrite, nitric oxide, ozone, and singlet O2, with emphasis on their redox properties. Subsequent chapters detail what antioxidants can be made in vivo (e.g. superoxide dismutases, peroxiredoxins) and which can come from diet (e.g. vitamins E and C, carotenoids, and polyphenols such as the flavonoids) and how they work in vivo. The role of RS in cell proliferation, senescence, and death (e.g. by apoptosis, necrosis, or intermediate forms) is presented. Methods for measuring RS are described in detail, including electron paramagnetic resonance and biomarker determination. Useful roles for RS (e.g. cell signalling, phagocyte action), as well as systems in which they cause particular problems (e.g. premature babies, the eye, the ear) are presented. Acute and chronic inflammation are used to illustrate both roles There is a comprehensive description of the role of RS in human diseases, from cancer to heart disease to dementia, in the ageing process, and in the toxicity of many agents, from ethanol to carbon tetrachloride to paraquat. Therapeutic agents active against RS are reviewed in detail, including NADPH oxidase inhibitors, N-acetylcysteine, and Ebselen.
In recent years, there has been an explosion of interest about the use of `antioxidant' nutritional supplements. Do they really defend the body against diseases? Should we all be taking vitamin E, vitamin C, or more of certain polyunsaturated fats? Written by two leading experts in the field of free radicals in biology and medicine, this book unravels the confusion caused by many nutrition-related claims, and clarifies the situation over whether maintaining high intakes of vitamins, minerals, and other food consituents really does help protect against life-threatening diseases.
Hydroxyl radicals, generated by reaction of an iron-EDTA complex with H2O2 in the presence of ascorbic acid, attack deoxyribose to form products that, upon heating with thiobarbituric acid at low pH, yield a pink chromogen. Added hydroxyl radical “scavengers” compete with deoxyribose for the hydroxyl radicals produced and diminish chromogen formation. A rate constant for reaction of the scavenger with hydroxyl radical can be deduced from the inhibition of color formation. For a wide range of compounds, rate constants obtained in this way are similar to those determined by pulse radiolysis. It is suggested that the deoxyribose assay is a simple and cheap alternative to pulse radiolysis for determination of rate constants for reaction of most biological molecules with hydroxyl radicals. Rate constants for reactions of ATP, ADP, and Good's buffers with hydroxyl radicals have been determined by this method.
Horse spleen and human spleen ferritins increase the formation of hydroxyl radicals (OH) at both pH 4.5 and pH 7.4 in reaction mixtures containing ascorbic acid and H2O2. The generation of OH is inhibited by the chelator desferrioxamine. Human spleen haemosiderin also accelerates OH generation in identical reaction mixtures, but is far less effective (on a unit iron basis) than ferritin under all reaction conditions. It is proposed that conversion of ferritin into haemosiderin in iron overload is biologically advantageous in that it decreases the ability of iron to promote oxygen-radical reactions.
Abstract Aerobic respiration is the process by whichO2 is used to oxidize foodstuffs (fats, carbohydrates, proteins) and produce heat and other forms of energy such as ATP. Because O2 is poorly soluble in water, the major constituent of the human body † we have evolved a transport protein to carry it, haemoglobin in the red blood cells (Figure 1). Haemoglobin has four protein subunits. To each is bound a complex chemical structure (haem), at the centre of which is an iron ion, in the ferrous (Fe2+) state. Oxygen reversibly binds to this iron, giving a Fe2+— O2 complex (causing the bright red colour of oxygenated blood).
